枣步曲幼虫排粪量的研究及应用

Studies and Uses on the Feces Quantity of Sucra jujuba Chu Larvae

本文采用野外罩枝放养幼虫以及观察林间样树上幼虫一昼夜自然落粪数等方法对危害枣树的枣步曲幼虫的排粪量的特性进行了研究 ,并应用排粪量来推算枣树上的虫口密度。结果表明 :枣步曲幼虫的排粪量与日平均气温及昼夜温度的变化密切相关 ,但各龄幼虫间变化不大 ;枣步曲幼虫的排粪量随着龄期的增长而呈几何级数增加 ;枣步曲幼虫在枣树上的分布比较均匀 ,各方位间无显著差 ;建立了以日平均气温和排粪量为自变量来推算出虫口密度的动态模型n =mF =m1 6849+0 81

The feces quantity of Sucra jujube Chu was studied in field and in covered jujube tree.it could be easily and reliably used to accurately determine insect density of Sucra jujuba Chu in jujube tree.The results were as follows The feces quantity of Sucra jujuba Chu larvae varies regularly with air temperature per day and temperature changes during a day,and differs insignificantly between ages of larvae;The feces amount increases in geometrical progression with ages of Sucra jujuba Chu Larvae;There is no great difference between directions owing to the well-distribution of Sucra jujube Chu Larvae in jujube trees.The dynamic model of insect density is built with mean temperature and feces quantity as the independent variables n=mF=m1 6849+0 8142T In that formula,'n'stands for insect density,'m'for the feces quantity per day,and 'F'for the mean temperature per day.